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That single case was brought up as a peculiarity, not as a recommendation to use SQLite under VM. It kinda jumps up when you've immensively better results in VM than native, that's what I meant with that first bit. It was a single case where VM seemed faster so I picked it up. Naturally native being tons faster than VM is uninteresting (except for CPU-bound tasks) since it's expected. What I continued with was that I intuitively assumed that reading an SQLite database file inside an image file on the hard disk would be slower than just reading a file on the hard disk. (on latter thoughts I'm not even sure if this matters, might not even significantly increase fragmentation)
Also read my message again: My conclusion was that virtual I/O needs to develop, not that real I/O needs to take example of virtual I/O. Even though the basis for my conclusion was wrong, the conclusion was apparently right.

For those people who have been on this thread, I dug around with the KVM and Ubuntu qemu-kvm maintainers.

It looks like "write-back" caching is turned on by default vs the recommended "write-through".

This increases performance and usablity, but it appears that it ultimately ignores requests for synchronous fileIO. Although this is the default configuration of Ubuntu currently, it effectively renders Ubuntu as not suitable for high-reliability workloads.

So the test was useful, and since it was clearly different than the other results, it has borne value by investigating.

Michael's assertions within the article are still correct. If you want a default SQLite install to absolutely fly, run it under KVM under Ubuntu. But be aware of the risk to your data - I personally don't expect Michael to invest in the way that I did to understand and present data for each and every unusual result.

Apart from raising a defect in Ubuntu, I see no interest in this benchmark. Who might see some interest in virtualization but companies? These companies would certainly not waste their forces in a system that is a) not fine tuned for virtualization at its best and b) based on a defect making the system unreliable. Maybe I'm too negative but that's how I see it.

Apart from raising a defect in Ubuntu, I see no interest in this benchmark. Who might see some interest in virtualization but companies? These companies would certainly not waste their forces in a system that is a) not fine tuned for virtualization at its best and b) based on a defect making the system unreliable. Maybe I'm too negative but that's how I see it.

I personally use virtualization to run Windows within a window under Linux. I switch between Vista and XP by just starting an image. With virtualbox, you can also access USB which gives you driver access to USB devices.

There are other reasons such as "near-disposable images" that you can copy rather than re-install, there is also the experimentation options by installing into a VM too.

These is definitely a user-oriented thing rather than corporate.

The trigger for the caching policy change was users complaining about performance. So I can't speak for Ubuntu, but there is a reasonably strong pull for them to invest.

For those people who have been on this thread, I dug around with the KVM and Ubuntu qemu-kvm maintainers.

It looks like "write-back" caching is turned on by default vs the recommended "write-through".

This increases performance and usablity, but it appears that it ultimately ignores requests for synchronous fileIO. Although this is the default configuration of Ubuntu currently, it effectively renders Ubuntu as not suitable for high-reliability workloads.

So the test was useful, and since it was clearly different than the other results, it has borne value by investigating.

Michael's assertions within the article are still correct. If you want a default SQLite install to absolutely fly, run it under KVM under Ubuntu. But be aware of the risk to your data - I personally don't expect Michael to invest in the way that I did to understand and present data for each and every unusual result.